Since there seem to be a huge amount of different topics posting different cheats, I figured it would be a good idea to make a list of all the ones found. To enter the cheats, you must go into Diagon Alley from The Leaky Cauldron and find the shop that sells spells, it should say "Wizarding Supplies" above the shop. The codes can be entered on the blackboard on the top floor of the shop.
~~ I'm not taking credit for these cheats, just listing them ~~
Please note that extras do NOT disable achievements. In fact, they are encouraged, so feel free to use them.

Thanks for the list, just one problem though. If you unlock any of the red brick extras, they won't show up on your red brick detector even thought you still need to grab them for the achievement. Not a big deal, just thought I'd point it out.

Here's a question: My son and I have completed 85% of the game on the Wii (probably 30 hours or more since he was 6-7 at the time). Is there any way I can enter the cheat codes as well as some of the controller combinations that unlock the levels from the main menu to unlock things on Xbox 360 to get us close to the level of completion we were at on the Wii so we can complete to 100% on Xbox 360, and through the process of entering the cheats, having it be a mass unlocking of achievements for us? Basically, will entering the cheat codes and controller combinations to unlock things unlock the achievements too? (I see questions always asking about cheats disabling achievements, but here I'm asking if the in-built cheats for the game will unlock the achievements after they are entered.)

I get that at least for the red brick achievement, we'll have to go back and actually find any unlocked with cheat codes which isn't a big deal. I'd like to avoid having re-play the whole game as we have the following LEGO games to complete all the way through (they're too much fun!): Batman, Batman 2, Harry Potter 5-7, and soon Marvel Super Heroes.

If we have to re-play to get the achievements we will, but if I can shortcut just this game for all the effort put in on another console, that'd be great. This is one situation where I wish the game had asked you for a login for a master account through the game publisher where if you played it on another console/PC, your account progress would be shared (a bit forward thinking for this game since it came out a while ago).

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